Back-stop for vehicles.



J. H. ADAMS. BACK STOP FOR VEHICLES. APPLICATION FILED JUNE 4, 1912.

JhQfl/W Q Patented July 15, 1913.

2 SHEETS-SHEET l.

WITNESSES l/VI/E/VTOR %efi James H.Aolams S W I By ATTORNEYS J. H.ADAMS.

BACK STOP FOR VEHICLES. APPLICATION FILED JUNIM, 1912.

.lhfijmu Patented July 15, 1913.

WITNESSES l/VI/E/VIOR Jams H.Adolms g v By M ATTORNEYS JAMES HARRISONADAMS, OF TAFT, CALIFORNIA, ASSIGNOR ONE-HALF T0 WILLIAM O. CLAY, 0F.TAFT, CALIFORNIA.

BACK-STOP FOR VEHICLES.

memo r.

Specification of Letters Patent.

Patenteddulyt5,1l913.

To all whom 2'25 may concern:

Be it known that I, JAMES H. ADAMS, a citizen of' the United States, anda resident of Taft, in the county of Kern and State of California, haveinvented a new and Improved Back-Stop for Vehicles, of which thefollowing is a full, clear, and exact description.

This invention relates to back stops for vehicles, and more particularlyto'a device mounted on a wheel of a vehicle comprising a rotatingmember, a pivoted member and means associated with same to control theengagement of the two members whereby the backing of a vehicle isprevented.

An object of the invention is to provide an inexpensive, simple andreliable back stop for vehicles which can be easily attached to thewheel of a vehicle and provided with a controlling lever or pedal forthe operation of the' device by the driver when desired.

A further object of the invention is to provide a back stop which isnormally in a non-operative position and will not modify or otherwiseaffect the operation of the vehicle.

The invention consists in the construction and combination of parts, tobe more fully described hereinafter and particularly set forth in theclaims.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the views, and in which- Figure 1 is asideelevation of a motor driven wheel for a vehicle, partly in section,embodying my invention; Fig. 2 is a sectional view on the line 2-2 ofFig. 1, in the direction indicated by the arrow, with the brake ribbonremoved; Fig. 3 is also a sectional view on the line 3-3 of Fig. 1, withthe bearing parts and brake removed; and Fig. 4 is a diagrammatic viewof the device in connection with the operating pedal.

Before proceeding to a more detailed de- ,scription of my invention itmust be understood that my device may be attached on any rotating memberof a vehicle, and the general relation of parts forming the device maybe differently arranged in accordance with special conditions, withoutdeparting from the underlying spirit of the invention.

Referring more particularly to the drawings, 1 is a driven wheel of amotor vehicle and 2 is a brake drum provided with a hearing case 3 andball bearings 4, 4, the whole ournaling on the shell 5 of the drivingshaft ('3. The brake drum 2 is also internally provided with a brakeribbon 7 pivotally attached to a bolt 8 and provided with means tooperate the brake, not shown in the drawings. The bolt 8 is fixed to astationary flange 9, which in turn is attached to the shell 5 and servesas a cover for the brake drum 2. Into the drum 2, fitting loosely overthe bearing case 3, a ratchet wheel 10 is rigidly attached to the saiddrum and the wheel by a plurality of bolts 11. Engaging one end of theratchet wheel 10 is a pawl 12 journaling in a bearing 13 and pivoted insame on a pin 14. The bearing 13 is rigidly attached to the stationaryflange 9 and is provided with an extending lip 15 against which a flatspring 16, fixed in the pawl 12, is bearing. The other end of the pawlis provided with a curved cam surface 17 engaging a cam 18 fixed on ashaft 19, journaling in the flange 9 and connected to a crank arm 20,which in turn is connected by a rod 21 to a pedal 22 and spring 23. Thespring normally holds the pawl 12 disengaged from the ratchet wheel 10.

Under normal conditions the position of the device is indicated indotted lines in Fig. 3, and it is easily understood that the backwardmotion of the vehicle is obtained without interference with the device.To operate the device pressure is applied to the pedal 22, forcing therack 21 (see Fig. i) to the left, as a consequence forcing the cam 18through the crank arm 20 and shaft 19 upward, thus permitting the flatspring 16 to turn the pawl 12 on the pin 14 downward into engagementwith the ratchet wheel 10, as shown in Figs. 2 and 3. It is easily seenthat the pawl allows only forward motion, as indicated by the. arrow Ain Fig. 3, and no backing of the vehicle is possible. The importance ofthis is easily seen when a dangerous hill is ascended by a vehiclesupplied with a device as described; no matter what happens to themotive power during the ascent of the hill the vehicle will only. stop,being prevented from backing, and cannot return to the foot of the hillata speed dangerous to the occupants of the vehicle, and other vehiclesas: cending or at thefoot of the same hill.

.end adapted to engage the ratchet wheel,

a spring member for forcing said arm into engagement with the teeth ofsaid ratchet wheel, the said pivotally mounted member a being providedat the other end with'an upwardly curved arm forming a cam surface, acam engaging the said upwardly curved cam surface, and means foractuating said cam to control the engagement of said pivotally mountedmember with thesaid ratchet wheel.

2. A device of the character described, comprising a drum, a ratchetwheel within the drum, the drum and ratchet wheel being adapted to besecured to a vehicle wheel, a pawl provided at one end with an armhaving a curved cam surface, the other end of said pawl being adapted toengage said ratchet wheel, a fixed bearing in which said pawl ispivoted, the said bearing having an extended lip, a flat spring betweenthe said pawl and the said lip and fixed at one end to the pawl, theother end of said spring bearing on said lip to force said pawl intoengagement with said ratchet wheel, a cam engaging the curved Surface ofthe arm of said pawl, and means connected with said cam for normallyholding the same in position to disengage the pawl from the ratchetwheel.

3.'A device of the class described, comprising a ratchet wheel adaptedto be secured to a vehicle wheel, a fixed bearing a-djacent theperiphery of the ratchet wheel, a pawl pivotally mounted in said bearingand having one end curved downwardly and adapted to engage the ratchetwheel, a spring for forcing said end of the pawl into engagement withthe ratchet wheel, the other end of said pawl being curved upwardly andforming a cam surface, a cam 'shaft mounted to turn and extending abovethe said upwardly curved cam surface of the pawl, a cam carried by saidshaft and engaging said cam surface of the pawl, a spring-controlleddevice connected with said cam shaft and normally holding said cam inposition to disengage the pawl from the ratchet wheel, and means foroperating said device to move the cam into position to per-' mit thepawl under the actionof its spring to engage said ratchet wheel.

4. The combination with a vehicle wheel, of a drum provided with abearing case journaled on the shell of the driving shaft, a stationaryflange attached to the shell of the driving shaft and formin a cover forthe drum, a ratchet wheel within the drum and fitting loosely over thebearing case, means for rigidly securing the ratchet wheel I to the drumand the vehicle wheel, a bearing within the'drum and rigidly secured tothe stationary flange, a pawl pivoted in said bearing, one end of saidpawl being adapted for engagement with the ratchet wheel, a springtending to hold the pawl in engagement with the ratchet. wheel, a camengaging the other end of said pawl, and means for actuating said cam tocontrol the engagement of said pawl with the ratchet wheel.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

Witnesses:

J. O. McCRoNY, E. D. KIDEILER.

JAMES HARRISON ADAMS.

